Neurology Book

http://www.fpnotebook.com/

Transient Ischemic AttackAka: TIA, CITS

Advertisement

  1. See Also
    1. Ischemic CVA
  2. Pathophysiology
    1. General
      1. Vascular related focal cerebral dysfunction
    2. Spectrum
      1. Transient Ischemic Attack (TIA)
        1. Temporary cerebral dysfunction
        2. Duration less than 24 hours (usually <10 minutes)
      2. Cerebral Infarction with transient signs (CITS)
        1. Partially reversible, non-disabling stroke
      3. Ischemic Cerebrovascular Accident
        1. Non-reversible stroke
  3. Causes
    1. See Transient Ischemic Attack Causes
  4. Risk Factors
    1. See TIA Risk Factors
  5. Symptoms and Signs
    1. Timing
      1. Carotid TIAs resolve within 14 minutes
      2. Vertebral TIA resolve within 8 minutes
      3. Symptoms persisting >1 hour: 14% resolve in 24 hours
    2. Anterior circulation symptoms (Carotid Artery)
      1. See Anterior Cerebral Artery CVA
      2. See Middle Cerebral Artery CVA
      3. Transient Monocular Blindness (Amaurosis Fugax)
      4. Clumsiness, weakness or numbness of hand
      5. Speech changes
    3. Posterior circulation symptoms (Vertebro-basilar)
      1. See Posterior Inferior Cerebellar Artery CVA
      2. See Vertebro-Basilar CVA
      3. See Posterior Cerebral Artery CVA
      4. Binocular vision changes or Diplopia
      5. Vertigo, ataxia or light headedness
      6. Dysarthria
      7. Generalized weakness
      8. Loss of consciousness
      9. Transient global amnesia
  6. Evaluation
    1. Urgently evaluate new onset TIA within hours to days
      1. Stroke follows TIA within 90 days in 20-25% of cases
      2. See Prognosis below for studies regarding risk
    2. History
      1. Evaluate differential diagnosis (see Ischemic CVA)
      2. Evaluate risk factors (see Ischemic CVA)
      3. Determine anterior or posterior circulation (above)
      4. Determine probable source (see causes above)
    3. Examination
      1. Thorough cardiovascular examination
        1. Assess for Carotid Bruit
        2. Funduscopic Examination
        3. Assess for Atrial Fibrillation
        4. Assess for Heart Murmur
        5. Assess for Hypertension
      2. Thorough Neurologic Examination
        1. Often normal if TIA has completely resolved
  7. Labs
    1. Complete Blood Count (CBC)
    2. Serum Glucose
    3. Serum Lipids
    4. Serum electrolytes
    5. Homocysteine
    6. Serum Folate
    7. Serum Vitamin B12
    8. ProTime with INR
    9. Partial Thromboplastin Time (aPTT)
    10. Hypercoagulable state evaluation
      1. Indicated in age under 50 years
  8. Radiology: First Line Evaluation
    1. Carotid ultrasound for anterior circulation
      1. Carotid Stenosis <50% suggests other source
      2. Carotid Stenosis >50% (especially if >80%)
        1. Obtain carotid arteriogram or MRA
        2. Arteriogram or MRA confirms >70% stenosis: Surgery
        3. Arteriogram or MRA suggests 50-69% stenosis
          1. Consider surgery in lower risk patient
          2. Medical therapy in high risk patient
    2. Transcranial ultrasound for posterior circulation
    3. Transthoracic echocardiogram
    4. Head CT or Head MRI
      1. Identifies prior infarction or hemorrhagic CVA
      2. Identifies Brain Tumor and other CNS masses
    5. Echocardiogram
      1. Transthoracic: Embolization suspected (see above)
      2. Transesophageal: Suspected emboli and negative echo
    6. Holter Monitor
      1. Identify suspected intermittent Atrial Fibrillation
  9. Radiology: Second Line Evaluation
    1. Magnetic Resonance Angiography (MRA)
    2. Arteriography
      1. Gold standard for pre-endarterectomy evaluation
  10. Differential Diagnosis
    1. See Ischemic CVA
    2. Hypoglycemia
    3. Migraine Headache (including aura)
    4. Seizure disorder (including post-ictal period)
    5. CNS tumor
  11. Management
    1. Immediate management of suspected TIA
      1. ER evaluation if symptom onset <48 hours ago
        1. See labs and radiology above
        2. See CVA Management if ongoing symptoms
        3. Consider for Thrombolytic management in CVA
      2. Urgent outpatient evaluation if >48 hours
        1. See labs and radiology above
        2. See Carotid Stenosis for Endarterectomy Indications
        3. See Prevention of Ischemic Stroke
    2. Inpatient evaluation criteria
      1. Cardioembolic source with Anticoagulation considered
        1. Acute MI with large wall motion abnormality
      2. Large or evolving Cerebrovascular Accident
        1. Severe neurologic deficit (e.g. dense Hemiplegia)
        2. TIA symptoms recurring at increasing frequency
      3. Vascular or neurosurgery consultation may be required
        1. High grade Carotid Stenosis suspected
        2. Possible Subarachnoid Hemorrhage
      4. High risk for CVA or TIA complications
        1. Aspiration Pneumonia
  12. Prevention
    1. See Carotid Stenosis for Endarterectomy Indications
    2. See Prevention of Ischemic Stroke
  13. Prognosis
    1. Adverse events occur in 20-25% with TIA within 90 days
      1. CVA represents 10% of these adverse events
      2. 50% of CVAs occurred within 2 days of TIA
    2. References
      1. Coull (2004) BMJ 328:326
      2. Johnston (2000) JAMA 284:2901
  14. References
    1. Pruitt in Goroll (2000) Primary Care, p. 970-4
    2. Beauchamp (1999) Radiology 212(2):307
    3. Biller (2000) Am Fam Physician 61(2):400
    4. Eugene (1999) {a 6611} 54(5):24
    5. Flemming (2000) Postgrad Med 107(6):55
    6. Hemphill (2000) {a 6611} 55(3):42
    7. Riggs (1998) Surg Clin North Am 78(5):881
    8. Ryan (1999) Am Fam Physician 60(8):2329
    9. Sacco (1998) Neurology 51:S27
    10. Solenski (2004) Am Fam Physician 69:1665

Transient Ischemic Attack (C0007787)

Definition (MSH)Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)
Definition (CSP)recurring, transient episodes of neurologic dysfunction caused by cerebral ischemia; onset is usually sudden, often when the patient is active; the attack may last a few seconds to several hours; neurologic symptoms depend on the artery involved.
Definition (NCI)A brief attack (from a few minutes to an hour) of cerebral dysfunction of vascular origin, with no persistent neurological deficit.
Definition (NCI)A brief attack (from a few minutes to an hour) of cerebral dysfunction of vascular origin, with no persistent neurological deficit.
ConceptsDisease or Syndrome (T047)
ICD9435.9
EnglishBrain TIA, Intermittent cerebral ischemia, Temporary cerebral vascular dysfunction, TIA, Transient cerebral ischaemia, Transient cerebral ischemia, transient cerebral ischemic attack, Transient ischaemic attack, Transient ischaemic attacks, Transient Ischemic Attack, Transient Ischemic Attacks
Spanishaccidente isquémico transitorio, accidente isquemico transitorio, AIT, ataque isquémico transitorio, ataque isquemico transitorio, ataques isquémicos transitorios, ataques isquemicos transitorios, disfunción vascular cerebral temporal, disfuncion vascular cerebral temporal, isquemia cerebral transitoria
CreditsDerived from the NIH UMLS (Unified Medical Language System)



Navigation Tree